The staff of the Neuropathology Core will coordinate brain autopsies, dissect and store autopsy brain tissues for research and perform brain cutting, diagnostic grading and morphometric and immunocytochemical evaluation on all autopsy cases of Huntington's disease (HD) and appropriate control cases. A new computer database will be established to record clinical and pathological data on each case. This information will be available to investigators in a manner that maintains the confidentiality of patient identification. Research tissue will be used by a number of different investigators, including those in this core and in Projects 4 and 5, and for RFLP studies of genetic linkage and presymptomatic testing families. The staff of the Neuropathology Core will devise tissue dissection protocols to supply optimally prepared tissue for the different research projects. A study of neuropathological diagnosis and histopathological grading in HD will be made, oriented toward improved diagnosis in cases with minimal pathologic changes and cases with confounding lesions such as stroke.